Powered garden tillage implement



Jan. 19, 1965 R, T BUTLER 3,166,140

Y OWERED GARDEN TILLAGE IMPLEMENT Filed sept, 16, 1963 5 Sheets-Sheet 2 mvENToR Rc1/ph 7'. BUT/er" Jan. 19, 1965 R. T. BUTLER 3,166,140

POWERED GARDEN TILLAGE: IMPLEMENT Filed Sept. 16, 1963 3 Sheets-Sheet 3 IIIIA'IIIIIA INVENTOR RC2/ph I Bu/er' BY Y M@ j J @Tram/frs.

United States Patent O 3,166,140 PWERED GARDEN THJLAGE MPLEMEN Rdph 'I'. Butler, 945 E. University, Springtield, Mo. Filled Sept. 16, 1963, Ser. No. 399,262 9 Claims. (Ci. 1813-19) This invention relates to a power driven, soil tillage implement, andrmore particularly, to such an implement of improved construction for use in gardens of small or generally limited areas.

It is the primary object of the present invention to provide a power driven, essentially one-wheel tractor suitable for use in garden tillage and which is simple to operate, economical to produce and maintain, and capable of being utilized for readily drawing any one of a number of different kinds of soil tillage tools over the ground.

Another object of the present invention is the provision of an implement of the type described which is constructed to permit easy steering thereof in diierent directions over the ground without the operator having to pit his strength against the power of the implement itself, whereby the implement may be more easily controlled than a conventional two-wheel tractor and especially while the implement is being turned.

Another object of the present invention is the provision of a one-wheel tractor which is provided with power means carried by the wheel itself, and furthermore, is provided with controls coupled with the power means and conveniently located rearwardly of the wheel for actuation by the operator whereby the implement forms a selfcontained unit which maybe readily controlled manually and guided by the operator walking behind the same.

Still another object of the present invention is the pro- Vision of an implement of the type described which is constructed with the power source therefor in direct alignment with the force resisting forward movement of the implement, i.e., the resistance resulting from the tillage tool of the implement engaging the ground, Vso that the power is more effectively utilized since the tendency for the machine to move to one side or the other of the line of draft, as has been the case in two-wheel tractorsfwhere the traction of opposed wheels against the ground varies, is eliminated and, as a result, the Work of tilling the soil may therefore be more effectively and easily performed by the implement of the present invention.

Yet another object of the present invention is the provision of a one-wheel tractor having a rotatable, groundengaging rim or wheel surrounding and supporting a frame carrying the engine therefor permittting not only a very eflicient and inexpensive drive connection from the engine to the rim but also allowing for pivoting of the rimV about a vertical axis so that the machine may be .steered while in an upright position.

Still another object of the present invention is the provision of a power source for an implement of the type described wherein the source utilizes an improved belt tightener in a manner such that the coupling of the engine to the rim may be controlled from the operators position remote from the engine and also permits the tensionof the belt to be maintained constant as the wheel is turned to steer the implement. y

A further object lof the presentinvention is the provision of height adjustment means on the implement of the Y above mentioned character so that tillage tools of various kinds may be accommodated on ythe implement and the latter may be adjusted for travel through the ground at any selected depth.

Still another object of the present invention is the pro-V vision of 'steering means for. an implement of the type Y describedl which permits maneuverability of the implement may be easily effected by the operator While Vthe depth of penetration of the tool on the vimplement through the transverse width thereof is maintained uniform even during the time that the wheel is being turned.

In the drawings: v

FIGURE 1 is a side elevational view of the implement Y of the instant invention and illustrating the use of a plow therewith; A Y

FIG. 2 is a top plan view. of the implement;

FIG. 3 is an enlarged, fragmentary, side elevational view of the frame and wheel of the implement with the prime mover forming the power `source of the implement removed from the frame, parts being in section to illustrate details of construction; Y

FIG. 4 is a cross-sectional view taken along line of FIG. 3

FG, 5 is a cross-sectional view taken `along line 5--5 of FIG. 3;

FIG. 6 is a cross-sectional View taken along line 6-6 of FIG. 5; Y Y l FIG. 7 is an enlarged, fragmentary, elevational view of the center section of one side .of the frame and illustrating structure for steering the wheel and frame over the ground;

FlG. 8 is a view similar to FIG. 7 but looking at the opposite side of the frame and illustrating the crank means for actuating the clutch of the prime mover;

FIG. 9 is across-sectional View taken along line 9 9 of FIG. 3;

FIG. 10 Vis an enlarged, side elevational View of the pinion interconnecting the rim or wheel of the implement with the power source and illustrating ratchet mechanism for releasably coupling the pinion to a driveV shaft; and

' FIG. ll is a cross-sectional view taken along line 11- within the wheel has a member pivotally receiving anV element secured to the wheel mounting structure so that upon manual operation of control mechanism on the handles of the machine and which are operably connected to the wheel bearing structure, the wheel may be easily turned from side to side as desired.

Structure Vis also provided for adjusting the, height of.

the steering structure with respect to the ground so that the operating depth of a tool on the implemement may be altered as selected by the operator.

The implement ofV the instant invention is broadly denoted by the 4numeral 26 and includes a single wheel A 22V mounted for rotation and in supportingrelationshipA to a frame 24 disposed Within wheel 22 and provided.

with guide structure 26 which. extends normally rearwardly of wheel 22 and frame'24 as is shown in FIG. l. A drawbar 28 also extends rearwardly of wheel 22 and frame 24 for coupling a suitable soil tillage tool 30 to frame 24. vHeight adjustment means 32 is pivotally coupled withstructure 26 to regulate the heightf'of the latter above theflevel 34 of the ground so that tool 30 may be moved under .the iniluence ofthe rotation of Y wheel 22 either in or out of an operative position in engagement with the ground. l

` in a forward direction of movement so as to draw tool FIG. 1.

Vtions of frame 24 to edect the steering of 30 along the'ground and to perform certain desired func- Y tions, depending upon the condition of the soil.

- result. spacer 96 orneach` bolt 94 maintains side plates Control means 3S carried at the rearmost end of'struci which are normally held in spaced-apartrelationship Vby Y a connector plate 44 which is normally horizontal and provided Ywith a pair of spaced, depending legs 46 on each ofthe side edges thereof'adjacent the inner surface of Vthe corresponding one of the side `plates '49 and 42. Legs 46 are each provided with a pair of threadedbores 48 which receive bolts Sti so as to secure the corresponding side plate to-plate 44.

Each of theplatesiil and 42 is provided with an opening 52 adjacent the normally upper extremity thereof as is clear in FIG. 3, openings 52 being aligned and receiving a normally horizontal platform-54 rigid to plate 44 as Vshown in FIG. 6.

VSource 36 is in the naturer of aYZ-cycle gasoline engine 56 having a fuel tank 5S coupled therewith in spaced relationship to the output or drive shaft'60 thereof.y Engine 56is rigidly secured toY platform 54 Withopenings 52 so` as to be suitably contained within wheel'22 as shown in As illustrated in(V FIG. 6, an axle 62 islte'lescopically received within a bearing 64V which in turn is received Within a sleeve 66 rigid to a transversely L-shaped member 68 forming a part of frame 24. Y Y

Each of the plates 40 and 42Y is provided with va gencorresponding opening 52 and is located below the latter. Member 63 is disposed within openings V76, the latter being aligned, and projects outwardly from side plates kerally rectangular opening 70 which opens up into the 4t) and 42 as shown in FIG. 2. By virtue of the construction shown in FIG. 6, laxle 62, and thereby plates'4ilV and Y 42, are rotatable about theaxis of hub of axle 62' with respect.,to'sleeve661and member 6 8. Sideplates 49 and 42 and member 68 are, therefore, relatively pivotal' pora manner hereinafter. described.

Wheel 22 is provided with Vafcircular rim'72 Vhaving al pair of spaced angle iron elements 74 rigid thereto on the inner surface thereof as shown in FIGS..5 and 9.

Each of the plates 4G and 42 is provided with arnumber implement 26 in of rollers 76 at'circumferentially spaced locations thereon as shown in FIGS. 1 andY 3, which rollers-76'bear against 4thecorrespondingelement 74 in: the manner shown in FIG. 9. To this end, each roller 76 is provided with, a pair of generally perpendicular surfaces 78 and 8G which complementally engage the corresponding faces of the respective elements 74, as shown in FIG.

9.` To this end, each roller 76 is rotatable about an .axis

Y`inclined with respect to the horizontal and is mountedon Ya bracket 82 having a rst leg 84 rigid to the corresponding sideplate 4b or 42, and a -second leg 86 which mountsroller 76 thereon byV means-oa bolt 88. A bearing permits roller 76 to rotate minimum amount of friction.

Each kof theplates 4G. and 42 is provided-with a notchv orslotf92 at each of the locations at which .a roller is disposed sov that Ythe plane of rotation. of yeachiof the Y `various rollers will be withirrtheY plane ofthe correspond- `ing side plate. Y j I Y H'Rollersm'76' of side plates 4i) and 42.` areg'enerally aligned so that corresponding Ybrackets S2 maybe'coupled connectrp'lates l40 and 42 and strengthens'nframe 24 as a on bolt 88 witha 4b and 42 a uniform distance apart.

By the use of'rollers 76 coupled with plates 4h and 42 1 in the mannerdescribed, rim '72 is mountedvon frame 24 for rotation is opposed directions about the central axis of rim 72; A series of cleats 98 are rigid to and project outwardly from the outerperiphery of rim-72 Y for'rwheel 22 when the latter engages to provide traction the ground.

Drive shaft 6d of engine 56'is provided with a sheave 1% over which a flexible, endless belt 1112 is trained. Belt 162 is also trained overa sheave 104 carried on a shaft 1516 spanning the distance between side plates 49 and 42 at a location spaced from openings 52 and 71),'V

as is clear in FIGS. Vl and 4. Bearings 108 journal shaft 1h56 on side plates 4Q and 42. I

A sprocket 110 is rigid to shaft 106 between'plates 4th and 42 and is coupled with anendless, flerrible chain 112 which -isy in turn trained over a sprocket-"114 having a diameter larger than the diameter of sprocket 119.

Sprocket 114 is carried by a shaft 116 and between side plates 40 and 42, bearings 11S being provided for journaling shaft 116 on plates 4t)` and 42.

. A sprocket 126 having a diameter small than sprocket 114, is rigid to shaft 116 and spaced, from a sprocket 122 rigid to a shaft 124 journaled in sideplates 40 and 42 by bearings-126. YVAn endless, evxible chain -128 is trained over sprockets 12@ and 122 as shown in FIG. 3. Ey virtue of sheave-1&4 and'sprockets 110, 114, 120 and 122, the speed of; rotation of shaft 124 is less than the speed of rotation of shaft 6i).-

A pinion 13), illustrated in FIGS..10 and k1l, is coupled to shaft 124 by means of a ratchet 132 and a pair of pins 134 floatingly held within ahousing 136 carried' by pinion and provided witha circular inner pe-l riphery having serrations defining a plurality of notches 144 as is clear in FIGS. 1Q and 11. Ratchet 132 is carriedby shaft 124 within housing 136 as shown in FIG. ll.V

Ratchet 132 is rigidly coupled with shaft 124 by a key 13S and provided with hook-like recesses Y144 for receiving pins 134 when ratchet 132rotatesin aV clockwise sense whenl viewing FIG. 10. Ratchet 132 isralso provided with a pair of generally diametrically opposed surfaces 142 which engage corresponding pins 134 and forcefthe latter into proximalnotches 144 onthe innerperiphery 136 of pinion 130 when ratchet 132 rotates in a counterclockwise sense, when viewing FIG; 10. Y

JJheii the ratchet 132 .rotates in a counterclockwise sense under ,the 'influence of the rotation of shaft 124, surfaces 142 .engage pins 134 to Vforce the latter into lthe proximal notches 144 and thus interconnect pinion 130 with shaft 124. VPinion 130,.therefore, rotates inthe same 'direction as shaft 124, the latter in turn being 'i rotated under the iniluence of drive shaft 60.A

engagement with surfaces 142, provided of course, Vthat Vshaft 124` is not rotating. When this occurs, pinion 130' is disconnected from shaft 124 and will remain so until ratchet 132 is again rotated by shaft 124.

A number of spaced, generally parallelpins 146'are secured in any suitable manner to and span the distance between'elements 74' inl spaced vrelationship tothe-inner surface of 72.1 A sleeve or roller v148 is rotatably It is evident that, when shaft 60 of engine 56 rotates, and when pins134 are positioned as shown in FIG. 10, pinionk 130 willbe rotatedina'counterclockwise sensetoin turn` 'Y p rotate rim 72fin a `clockwise sensewhen viewing FIG. 3Q togetherV by a single 'bolt-94 which'also serves to inter-V .Wheel `22 will then be ymoved forwardly over the ground to draw tool 3() therey'vith.v

When pinion 130.1otates in a clockwisesense when l viewing FIG. -l0, pins 134 are moved therewith out of tion rearwardly of wheel 22 as shown in FiG. 1.

Belt tightener mechanism 150 is coupled with belt 192 for alternately applying tension to Iand removing tension from belt 102 to thereby provide a clutch arrangement between sheaves 181B and 164. To this end, an arm 152 is pivotally coupled at one end thereof to plate 48 adjacent the outer face thereof by means ofa pin 154 for rotation about an axis parallel to shaft 68. A sheave 155 is journaled on the opposite end of arm 152 by a pin 158 and is movable into and out of engagement with belt 102 to alternately apply tension to and remove tension from the same. When tension is applied to belt 162 by sheave 15o, sheave 104 is driven by sheave 10i) through belt 192. When tension is removed from belt 162 there is no driving connection between sheaves 160 and 104.

A rod 169 is pivotally coupled adjacent one end thereof to arm 152 intermediate the ends of the latter. The

through :an arcuate slot 168 in plate 40 before projection 166 is pivotally coupled with bar 162.

Bar 162 is provided with a bearing mount 178 which, in turn, is provided with a bearing coupled to a clevis 172. A link 174 is pivoted to clevis 172 by a pin-176 and to another link 178 by apin 188. Link 178 is pivoted to a clevis 182 by a pin 184, clevis 182 being coupledV with abearing 186 received within a recess 188 in the lower surface of axle 62. A plate 19t) is secured by bolts 192 to the underside of axle 62 to retain bearing186 in place. Both axles 62 and bar 162 are rotatable with respect to links 174 and 178. Y Y

Pin 180` is integral with 1a rod 194 extending laterally from links 174 and 178 and through an opening196 in plate 42 as is clear in FIG. 5. The opposite end of rod 194 is pivoted to a generally C-shaped bracket 198 pivoted by means of a pin 260 to thel underside of member 68. A strip 202 extends laterally from bracket 198 and toward plate l42, but terminates in spaced relationship to the latter. strip 292 and extends rearwardly of wheel 22, as shown in FIG. 4. Rod 264 is `coupled with structure 26 in a manner hereinafter described.

Drawbar 28 includes a pair of spaced, 'generally parallel Iarms 206 of angle iron stock, rigidly secured to the outer ends of member- 68 and extending in a direc- The rearmost ends of arms 206 terminate rearwardly of rim 72 and are interconnected by a perforated crosspiece 288 also of angle iron stock.

' Tool 38, for purposes of illustration only, comprises a plow 210 having a generally upright plate section 212, and a share and moldboard Vsection 214 rigid to section 212. An L-shaped'connecting member 216 is rigid to plate section 212 and is releasably coupled by means of a coupling member 218 to crosspiece 288 of drawbar 28. A pin 228 passes through member 218-and through any one of a number of theperforations V222 in crosspiece 2&8 to secure tool 38 to drawbar 28.

Although a tool 38 in the nature of a plow, has been illustrated, it is to be made clear that any tool for tilling Vthe soil may be coupled to drawbar 2S and drawn over the ground by the rotation of wheel 22. .n

Guide structure 26 includes a pair of beams 224 of angle ironV stock secured at proximalends thereofrto the outer extremities lof member 68, as Vshown in FIGS. 1 and 2. Beams V224 extend upwardly and rearwardly of the interconnection thereof with memberV 68 and, as shown in FIG. 2, the major portions of beams 224 are relatively divergent as the outermost ends thereof are approached. A strip 2,26 of rigid material, intercornects beams 224 adjacent the outermost ends thereof, and a A rod 284 is rigid to the inner end of Y low the same.

Y-shaped support member 228 releasably and adjustably interconnects member 216 with beams 2724. To this end, member 228 is provided with alower leg 230 pivotally vcoupled'to member 216, and a pair of generally divergent arms 232 having spaced holes 234 along the lengths thereof for receiving pins 236 which interconnect arms 232 with the proximal beams 224. The distance between beams 224 and member 216 is thus controlled by the setting of arms 232 on beams 224.

Adjusting means 32 includes a sleeve 238 having a pair of arms 249 secured to and extending upwardly therefrom toward proximal beams 224. Arms 240 are relatively divergent and are pivotally coupled to proximal beams 224 by pins 242 to mount sleeve 238 be- A pair of arms 244 are secured at the lower ends thereof to sleeve 238 and extend forwardly and upwardly of the latter and connect with beams 224 by means of pins 236. Arms 244 work in conjunction with arms 2411 to maintain sleeve 238 in a vertically disposed position.

' A stem 246 is telescopically received within sleeve 238 and extends vdownwardly therefrom. Stem 246 is provided with a bifurcated lower end 248 and rotatably receives a ground-engaging wheel250 coupled therewith by means of a pin 252.

A shaft 254 is carried by a crosspiece 256 secured to and spanning the distance between beams 224. A pair of brackets 258 rigid to crosspiece 256, journals shaft 254 for rotation about the axis of fthe latter. A' first crank arri-1.268 is rigid to and extends generally downwardly and-rearwardly of one end of shaft 254.l A link 262 is pivotally connected to the outerend of arm 260 and adjacent the lower end of stem 246. as'V shown in FIG. 1.

A second crank arm 2d4 is rigid to and extends upf wardly ,and generally forwardlyof the opposite end of shaft 254 and is pivotally coupled with a rod 266 which extends rearwardly of arm 264 and pivotally coupled at the rear endv thereof with a control stick 268 pivotally mounted on the proximal beam 224 by a pin 270 and ears 272. Y Movement of arm 268 rearwardly ofv wheel Z2 causes stem 246 to be lowered with respect to sleeve 238 to in turn lower wheel 25) with respect to beams 224. VMovement of control Vsticks 268 in the opposite direction causes wheel 258 Vto be raised with respect to Y beams 224.

Rod 204 extends rearwardly of wheel 22 and terminates y adjacent and above strip 226. The rearmost end of rod 284 is coupled to an L-shaped control stick 274, the latter in turn being pivotally coupled on strip 2,26 by means of a pin 276 spaced above the upper surface of strip 226 by ears 278. By rotating stick 274 in a counterclockwise sense, when'yiewing FIG. l, rod 204 is pulled'rearwardly to cause bracket 198 to rotate in a direction to shift rod v194- to the left when viewing FIG. 5. This, in turn,

causes bar 162 lto be pivoted in a clockwise sense when viewing FIG. 3 to, in turn elevate sheave 156 out of erigagement with belt 102. Movement of control stick 274 forwardly with respect to wheel 22 causes rod284 Valso to be moved forwardly to rotate bracket 198 in the opposite direction and force rod 194 to the right Vwhen.,viewing FIG. V5. Y This, in turn, causes, bothvbar 162 and-sheave 156 to swing. downwardly to in turn cause tension vto be applied to belt 1532. Y

A throttle control lever 2813 is carried on strip 226 adjacent one end thereof as Vshown in FIG. 2 audris coupled. bymeans of a exiblercable 282 to the throttle controlY on engine 5d. Y

A pair of rods 284 are carried by beams 224 for ro`- proximal beam 224. A crank arm 28Sris rigid tothe forwardmost end of the proximal rod 284 and is provided vFIG. 5. Y v

A rod 292 havinga projection extending through sloty Y tion relative to member 68.

. shifted relative to member 63.

- plates 40 and 42 to the left.

299,' extends laterally of arm 28% toward the proximal side plate 40 or 42.. `An eyelet 2124 is rigid to the corresponding side plate 40 or 42 and pivotally'receivesfthe normally downwardly projecting, proximal end 2%ofrod 292. A handle v29S is rigid to the outer ends of each of rods 284 respectively. Rotation of rodsr284 by an operator Y grasping handle 298, is suicient to cause side plates 4t) and 42 to be shifted together in the corresponding direc- Since rim '72 is carried by side plates 4@ and '42the'direction of forward movement of rim 72 will be altered when side platesto and 42 are In this way, the steering I n As mentioned above, the makingof turns is effected b y Y rotating rods 234 upontwisting of handles '2%. When the operator vdesires to puil implement 26' rearwardly,

' sleeve 156'is moved out of engagement with belt 102 by shifting control stick 274 rearwardly, at which time shaft.

. 124 ceases to rotate..V A slight rearward movement of operator need, therefore, to expend only a minimum of of wheel 22 is effected and theoperator of'implement 2i) Y' does not need to ght the implement or pit his strength against the power applied to rim 72 and Vgenerated by engine 56. v

VIn operation,vtool 39 is coupled to VVdrawbarV 2S and, as mentioned above, tool 30 may be any one cfa number ofA so gthat wheel 250'will move along the` ground and Vtrack with Vwheel 22 without requiring thatv the operator of implement support the rear. ends of beam 224.V Y*

VUpon actuation of engine 55, power is delivered to rim 72 by shifting control ystick 274 forwardly to in turn cause sheave 155 to engage belt 162 and apply tension to the latter. This, in turn, causes pinion V131) to rotate in a counterclockwise sense when viewing FIG. 3, since ratchet v different kindswof soil tillage devices.' The height of wheel V 259 may be adjusted by manipulating control stick 25S;

energy to move implement 20 rearwardly. v

The present invention provides a self-contained one;

wheel tractor having the `prime mover or power source mounted on the ground-engaging wheel thereof so as to take up a minimum of space, while atthe same time,H

lplement 2t). The'position of wheel `22 with respect Vto tool 36 issuch as to utilize'vthefmaximum power gen# erated by source'S since toolV Si) is generally in Valignment with the path of travel over the'v ground of wheel 22.

The 'steering characteristicsof implement 20. render the same especially suitable for use in gardens of small or generally'limitedareas, since the operator need not iight the implement 2li in order/to maintain control of the same.

. The steering structure'of the Ypresent inventionpermits 132 will immediately move counterclockwise withrshaftV l 124 andr surfaces 142V of ratchet 132 will force pins 134 into notches 144 to interlock shaft k124 and pinion 139.

Upon rotation of pinion 13th-rim 72 will begdriven in aforward direction over the ground and, by virtue of cleats 98,l the implement 20 will -beV driven-With rim 72.

The speed'of implement 20 will be controlled by lever 28) gagement with belt 102 by virtue of the factthat the longiimplement 20' to beV highly maneuverable so that'- a given job maybe performed in a minimum of time and with a minimum expenditure of'energy `on the part ofthe Voperator of implement`20. l v

It is clear that the present invention is not limited to the l use of soil tillage tools. j For instance, a mowingattachment could be coupled to implement 20 either at the frontY vIt is to be noted that sheave 156 -is maintained'in enend or rear end thereof for the mowing of grass, weeds and the like. Also, a blade could be coupled to the front or rear end of implement 20` for snow removal purposes or for moving grain from place-to-place.

tudinal axis of rod 204 passes to one sideof'pivot 276V` is manually pulledV rearwardly. Y

To .eiect turning movements of wheel 22 the operator rotates-rods 284 by twisting handles 298 in the samedirection. For instance, if it is desired` to turn wheel'22 to the right, the operator will rotate rods 284 lina clockwise coupling control stick 274 to ears 278.l Control stick 274 Yis thus effectively and releasably lockedvin place until it Y Wardly of axle 62,the forwardmost portion ofwheel 22Y will turn to the right and rimf72 will move in the corresponding direction. Conversely,` rotation or, rods 284 in a countercloc'kwisersense will cause wheel22 to turn tok the left. Y

Itis noted that when side plates' and 42 pivot relative to member 68, axle 62 rotateslwith pleats 40 and 42 and relative to links 174and 17S. Hence, bearing l136 `is Similarly, since'bar required to permit' this movement; 1752 is' coupledto side `plates 49 and 42, it also will 'shift therewith and Will shift relativeV to links k174 and 17S.

'Y Thus, it is evident that the bearing of mountv 17) is re.

`quired. Y

implement 20 K andfrom arpoint ofruse by manipulating control stick 26S may be readily movedrover the ground to so as to lower and raise wheel 250. By lowering wheel.`

ment 20k may then be readily moved from place-to-place for subsequent use. Likewise, tool tl'may belifted-with 1 v Y rotatable about itslongitudinal axis, and a link pivotally implementr2ti preparatory toV making another pass over the ground.

[Having thus` describedY the invention, what 1s claimed as new and desired to be'secured byLetters Patent is:

1. A tractor unit adapted to be coupled to a work attachment comprising: n Y Y a frame having anouter periphery;

a ground-engaging wheel rotatably imountedin an upt rright position on the outer periphery: of said frame Y wheel; z h drive means carriedby the frameyand operably coupled` with said wheel for rotating the latter; Y a mounting member extending laterally from the frame beyond the latter;

elongated guide structure alongside the wheel connected to said memberV and extending rearwardly therefrom; mounting means within the perimeter-of said wheel and rotatably securing saidl frame Yto the member for pivotal movement ofthe frame relative to the V`member and guide structure about a vertical axis in intersecting relationship to said wheel axis; v. control means carried by said guide structure and'coupled with. said frame for pivoting'thelatterv and there- Vby said wheel relative to said guide structure about said vertical axis; and Y drawbar means for coupling a work attachment to said Y. mounting member. j Y v y 2K. A tractor unit as setV forth in claim 1*,.wherein said Vcontrol means includes a rod carried by said Vguide struc- Y ture and extending longitudinally'thereof, said rod being means, Ywhereby said' frame is` pivoted relative Yto said n for rotation relative thereto about the axis of the 9 guide structure and the mounting member as said rod is rotated about its axis.

3. A tractor unit as set forth in claim 1, wherein said mounting means includes a normally vertically disposed axle and bearing means on the member mounting the latter on said axle for pivotal movement about the axis thereof.

4. A tractor unit as set forth in claim 3, wherein said axle is rigid to said frame', is disposed with its longitudinal axis substantially perpendicular to said wheel axis and said bearing means includes a sleeve rigid to said member, said axle being disposed within and rotatable with respect to said sleeve. Y

5. A tractor unit as set forth in claim 1, wherein said drive means includes a power source secured to said frame in generally overlying relationship to said mounting means.

6. A tractor unit as set forth in claim 1, wherein said frame includes a pair of spaced interconnected side plates, said mountingmeans being disposed between said plates.

7. A tractor unit as set forth in claim 1, wherein said drive means includes a clutch arm mountedron said frame for movement with respect thereto into and out of an opperative position, and linkage structure shiftably carried by said guide structure., pivotally connected to said clutch arm for moving the'latter into and out ofsaid position as said linkage structure is shifted in opposed directions rela-V tive to saidl guide structure and as the frame rotates relative to the linkage structure, said linkage structure being operable to maintain said clutch arm in said position as said frame pivots relative to said member and the guide structure.

` 8. A tractor unit as set forthzin claim 7, wherein said linkage structure includes a reciprocable rod and pivot' means coupling said rod to said clutch arm to permit rotation of the frame and said clutch arm relative to said rod without movement of the latter, said rod being movable 10 independently of the frame to shift said clutch arm to and from said position thereof.

9. A tractor unit as set forth in claim 8, whereinsaid pivot means includes a pair of links adjacent said mounting means, interconnected at proximal ends thereof and lying on said vertical axis of pivoting of the frame Vwhen in aligned relationship to present a toggle, said rody being pivotally coupled at one'end thereof to said links to shift Vthe Vlatter relatively and thereby openand close the toggle in response to reciprocation of the rod, and wherein is included bearing means coupling one'of the links tothe mounting means whlepermitting free rotation therebetween, connector means operably joined to said clutch arm .for swinging the latter to and from said position thereof as the connector means is moved, and bearing means joining the other link to said connector means while permitting free relative rotation therebetween whereby the clutch armrnay be shifted to and from said positionby reciprocav tion of the rod independently of swinging of the frame relative to the mounting member.

References Cited bythe Examiner UNrTED' STATES PATENTS Anderson V 19 A. HARRY LEVY, Primary' Examiner. Y RUSSELL R. KINSVEY, Examiner. 

1. A TRACTOR UNIT ADAPTED TO BE COUPLED TO A WORK ATTACHMENT COMPRISING: A FRAME HAVING AN OUTER PERIPHERY; A GROUND-ENGAGING WHEEL ROTATABLY MOUNTED IN AN UPRIGHT POSITION ON THE OUTER PERIPHERY OF SAID FRAME FOR ROTATION RELATIVE THERETO ABOUT THE AXIS OF THE WHEEL; DRIVE MEANS CARRIED BY THE FRAME AND OPERABLY COUPLED WITH SAID WHEEL FOR ROTATING THE LATTER; A MOUNTING MEMBER EXTENDING LATERALLY FROM THE FRAME BEYOND THE LATTER; ELONGATE GUIDE STRUCTURE ALONGSIDE THE WHEEL CONNECTED TO SAID MEMBER AND EXTENDING REARWARDLY THEREFROM; MOUNTING MEANS WITHIN THE PERIMETER OF SAID WHEEL AND ROTATABLY SECRUING SAID FRAME TO THE MEMBER FOR PIVOTAL MOVEMENT OF THE FRAME RELATIVE TO THE MEMBER AND GUIDE STRUCTURE ABOUT A VERTICAL AXIS IN INTERSECTING RELATIONSHIP TO SAID WHEEL AXIS; CONTROL MEANS CARRIED BY SAID GUIDE STRUCTURE AND COUPLED WITH SAID FRAME FOR PIVOTING THE LATTER AND THEREBY SAID WHEEL RELATIVE TO SAID GUIDE STRUCTURE ABOUT SAID VERTICAL AXIS; AND DRAWBAR MEANS FOR COUPLING A WORK ATTACHMENT TO SAID MOUNTING MEMBER. 